[Sprint/RollingRabbit](fix): Save draft button vanishing in blogs #2186

Closes #2186 (closed)

Summary

Currently, the "Save draft" button is vanishing in blogs in two scenarios.

1. As in the issue above; when you trigger an error by not inputting a title or banner.
2. When you hit publish, but it is rejected.

Testing

1. Make a blog with no banner
2. (click) Publish
3. (click) Save Draft
4. Both should return the error and neither button should disappear
5. Add the missing item (banner or title).
6. (click) Save Draft
7. Try to edit the blog again when its saved.
8. Verify you can publish and or save as draft
9. (click) Publish
10. Verify that you can no longer save draft.